US1502169A - Electric tool - Google Patents

Description

C. B. BENNETT ELECTRIC TOOL Filed Nov. 5, 1921 v 2 Sheets-Sheet l N Nh. NQ. .E

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July 2z, 1924. 1

' C. B. BENNETT ELECTRIC 'TOOL Filed NOV. 5 192] 2 Sheets-Sheet 2 and is mounted on a removable head provide for 3o ism from the` switch in veniently closed for 5o ticularly pointed out` in the Patented July 22, 1924- UNITED STATES PATENT OFFICE.

CHARLES B.. BENNETT, OF LOUISVILLE, KENTUCKY, ASSIGNOR TO JAMES CLARK, JB. ELECTRIC COMPANY, OF IUISV'ILLE, KENTUCKY, A CORPORATION OF KENTUCKY.

ELECTRIC Toor..

Application led November 5, 1921. Serial No. 513,037.

10 cludes electric motors, and an object'of the invention is to rovide such a tool with an improved hand e shaped and arranged to facilitate the manipulation of the tool. The.

handle is of the type used on hand-saws, of the motor casing, whereby the `handle is removed with the removable, head whenever access is to be'had to thel motor.

A further'object of the .invention is to conveniently actuating the electric switch for starting and stopping the operation of the motor, and also to enable the actuation of the switch by the operators hand which holdsI or grasps the handle. j I

25 mount. the switch and all electrical connec- -tions on the motor casing, while the switch actuating mechanism is mounted on S the han le, provision being made for convenient disconnection ofthe actuating mechan- 4 order that the removal of the handle 4may not disturb the switch nor'any of the electricalconnections. When. the tooll is not in operation, the switch is ofcourse open and may be constarting the motor merely by pressing uponA the actuating lever mounted upon the handle. On releasin the lever, which is spring pressed), the switcl will be snapped into its open position so as 4o to :sto thefmotor.D Provision is also made where y the switch may 'be Amaintained close; without re uiring the operator to hold the actuating sit-ion.4v u

lWith these and other objects in'view, the

' present invention consists in the combination` and arrangement of parts as will be hereinafter more fully described, illustrated in the accompanying vdrawings and parappended a1ms, it `of course being understood that changes in the form, proportion, size andI minor Ydetails may be made, within the sco e of the claims, without departing from t e 'form but preferably in the form of an ings indicated in ever in its retracted po 'housed within the casing spirit or/,sacricing any of the advantages of the' invention.

In the drawings:

Figure 1 is a side elevation of an electric tool embodying the features of the present invention, theA handle and the switch casing being in section to expose the electric switch and the actuating lmechanism therefor.

' Figure 2 is a side elevation, on an enlarged scale, of the switch removed from the motor casing.

Figure 3 is a bottom plan view of the switch with the casing' in section.

Figure 4' is a side elevation looking at the opposite side of the tool from that shown in- Figure 1.

Figure 5 is an enlarged detailedperspective View of one of the switch elements.

Figure 6 is a detailed perspective view of the bell crank link or member ofthe toggle portion of the switch.

Figure 7 is a detailed perspective view of the spring actuated link or member of the to e.

igure 8l is-.a detailed fragmentary view illustrating'the positions of the toggle mem.

tor lof the tool, not shown, is contained Y within a motor casing 1 of any desired o en ended cylinder provided with a front premovable head 2 and a rear removable head 3, each off said heads being detachably held in place by suitable screw threaded fastenable tool spindle 5 projects longitudinally at the front-of the casing and is equipped with a suitable chuck 6 to -which an appropriate form of drill or tool may he fitted in the usual manner. By reason of the fact that the heads 2 and 3 may be removed, access may be' conveniently had to the motor In carrying out one of the features of the presentinvention, a handle is provided upon the rear removable head 3, this handle preferably being .of the type commonly dotted lines at 4. A suit- 13 and the block 16.

employed upon hand-saws and includes a grip or cross-bar 7 connected at its top and bottom with the removable head 3 by means of the connecting elements 8 and 9. While not necessary, I prefer to form the head 3 and the parts of the handle as an integral casting. With a handle of the form shown in the drawings, very convenient manipulation of the tool may be had, as the entire tool lnay be held in one hand and pressure applied directly to the rear end of the tool in the most'eifective and satisfactory manner.

While any desired form of electric switch may be. employed tor starting and stopping the motor, a satisfactory switch construction has been shown in the drawings. This switch mechanism includes a base member 10 fitted flat against the bottom of the motor casing and secured thereto by suitable astenings 11 extending through perorated ears 12 projecting laterally from said base member. Extending along each edge of the base member is a depending iiange 13 which extends beyond the rear of the member and is deiected downwardly to form an arm 14. The two arms 14 constitute a fork or yoke at the rear end of the base member 10. Each of the flanges 13 is provided with an outwardly directed shoulder 15 formed by bending outwardly a portion of the iiange. A block of insulating' material 16 is disposed between the anges 13 and secured thereto by suitable fastenings 17 extending through the flanges A contact member 18 is suitably secured to each side 'of the block 16 and has a finger portion 19 projecting rearwardly at the rear end of the block. suitable binding post 2O is provided for each of the contacts.

Electric connection is established between the two finger-portions 19 of the two contact members 18 by a snap device in the form ot a toggle including a bell crank member 21 made up'ot a pair of duplicate segmental plates 22 connected at their rear edges by a cross-bar or plate 23. This bell crank member is received between the arms vof thefork or yoke 14 to which it is pivoted as at 24 in Figures 1 and 2. Suitable stop projections 25 arise `tromv the top edges of the plates 22 and overhang the top of the yoke arms 14 so as to contact therewith and limit the pivotal movement of the bell crank member in one direction. In front of the bell crank member is a link 26 made of insulating material and slotted or bifurcated longitudinally to form yoke or fork arms 27 which are received between'. the side members 22 of the belll crank. Each of the fork arms 27 is provided with a notch or seat 28 receiving a pin or projection 29 extending inwardly rom the adjacent side wall 22 of the bell crank lever.- A helical spring`30 is disposed in the slot or bifurcation of the link 27 and has one end Aconnected toa pin 31 extending through the bifurcated portion' of4 the link, vthe other end ofthe spring being connected to the pivot pin 24. Normally the position of the A lthe spring 30 is moved across the center,

whereupon the pins 29 will become the pivotal support for the rear end of the toggle link 26 and the latter will be snapped downwardly to the position shown in dotted lines 'in Figures 1 -and 2` with its members in engagement-.with the contact fingers 19. thereby establishing an electric connection between said finger-portions 19. permitting current to flow from one of the elements 18 to the other element 18 through the conducting rollers 32 and their connecting pin or axle 32. This is the. closed position of the switch which starts the electric motor and maintains it in operation.

The means for manually actuating the snap switch includes a lever 33 mounted within the hollowA handle 7 and inserted therein through a slot 34 in the inner tace of the handle. This lever is fulcrumed in termediate of its ends as at 35 and has its lower end connected to the lower end of the bell crank 21 by means of a connecting -rod 36 pivoted as at 37 to the bell crank and connected to the lower end of the lever 33 by means of the removable pivot pin 38. The connection'38 is preferably a screw threaded pin capable of being removed, for convenience in connecting and disconnecting the link or rod 36 to the lever 33. Aceessto the removable fastening 38 is obtained through an opening 34 in the handle. The upper end of the lever 33 normally lies in front of the handle and is laterally enlarged to"form a lfinger piece orl grip 39. A compression spring 40 is fitted within a seat 41 in the handle 7 and bears against the rear side of the lever 33 adjacent the upper end of the finger piece portion thereot` so as to normally and yieldably maintain the lever in thel position shown in Figure with the switch in its open position. open at its rear end and is provided with a closure 42 in the form of a screw'plug whereby the spring may be conveniently tted inplace and removed.

The tool is provided with a cable 43 of suitable length and provided at its free end The seat 41 is Hill start the motor,

Amoana with a plug or suitable connector. This cable is secured to the motor casing by a suitable clamp or bracket 44. One of the conductors 45 leads`from the cable to one of the'binding posts 20 while the other conductor'46 4leads to a binding post 47 pro,- vided upon the bottom of the casing and connected inside of the casing to the motor in any well known or approved manner. A conductor 48 leads from the other binding post 20 upward] through the bottom of the casing and to t e motor in any approved manner.

With the parts in positions shown byfull lines in Figure 1 of the drawings, it will be understood that the switch is open. To

the operator takes the liandle 7 in one hand and presses against the fin ger piece 3910i the switch actuating lever 33, whereby the lower end of the lever will be moved forwardly to the dotted position carryin with it the link or connecting rod 36 whic will turn or rock the bell crank 21 to the dotted osition which, ashereinbefore described, wil resultin the breaking of the tog le, formed by the bell crank 21and the li 26, whereby vthe latter will be snapped down into engagement with the contacts 19, thus closin the switch and starting the motor. So ong as the pressure of the hand remains upon the lever 33, the

switch will be maintained closed and the motor continued in o eration. Upon relieving pressure from t e linger piece 39 of the lever 33, the spring 40 will return the lever 33 to its normal position, whereby the link or connect/ing rod 36 will be pulled back to its normal position, the toggle will be broken downwardly and the link 26 will be snapped upwardly into its normal full line position, whereby the switch will be open and the motor will be stopped. Y

The s 'tch may be maintained closed and the motor in operation by thrusting a pin or other device into the openingf 34 in the handle 7 and in rear of the lever 33 so as to maintain the same in its dotted position.

The same result ma be accomplished, reference being had to igure 4 of the drawing, by thrustingl a pin or the like into an opening 49 in t e casing 50 which incloses the switch, said in overlyin the free end portion of the link 26 and olding it down in en a ment with the contacts 19.

enever it is desired to remove the handle or to have access tothe motor, the pivotal connection 38 is removed through the opening 34 in the handle, andthe fastenings 4 are removed from the head 3, whereupon the latter, the handle and the mechamsm contained therein, with the exception of the link or rod 36, may be withdrawn from the cas' and the switch .without in any mannerl'xdgisturbing 'the latter electrical connections. A

' casing and or any of the.-

` v through the slot in the handle, a spring to l front of and also independent of the handle 7 theseveral parts of the tool may be assembled, and prior to fitting the handle i BB1/mounting the -switch on the casing 1 i 1n in glace, the motor and switch may be tested,

ing, a tool spindle projecting at one end of the casing, a removable handle for the casing, an electric switch for starting and stoping the motor and mounted upon the motor casing, and located in front of the handle, and a hand-operated switch-actuating means carried by the removable handle and detachably associated with the switch.

2. An electric tool comprising a motor casing, a tool spindle rojectin at one end of the casing, a remova le hand e for the opposite end of thecasing, a lswitch for starting and stopping the motor and carried by the casing vand in front of the handle, a hand-operated lever fulcrumed upon 'the handle, and a detachable operatin connection between the lever and the switc 3. An electric tool comprising a motor casing, a tool spindle projectin at oneend of the casing, aremovable-hea for the opposite end of the casing, a handle carried by the removable head and provided with a longitudinal slot, a switch forstarting and4 stopping the motor and mounted upon the motor casing, a hand' operated lever fulcrumed within the slot portion of the handle, a connecting member between the lever andthe switch, and a detachable pivotal connection between the'connecting member and the lever;

V4. An electric tool comprisingj a motor casing', a tool spindle projectin at oneend of the casing, a removable headr for the opposite end of the casing, a switchfor starting and stopping the motor and mounted on the casingand located in front of the handle, a-handle 0f the hand-saw type carried by the removable head, a lever fulcrumed upon the vhandle and having a finger portion lying between the handle and the removable head, and a detachabley connection between the lever and the switch.

5, An electric tool comprising a motor casing, a tool spindle projectin at one end of the casing, a removable hea for the oposite end of the casing, a handle of the and-saw type carried by the removable head, the ip portion of the handle bein hollow an provided with a longitudina slot in its' front face, a switch forv starting and stoppin the motorandmounted on the located in front of the handle, a lever fulcrumed vwithin thewhandle and having a nger portion extending outwardly ieldably maintainjthe finger portion of the ever in its forward position, and a link detachably connecting the other .end of the lever with the switch.

'6. An electric tool comprising a motor casing, a tool spindle projecting at one end of the casing, a handle at the opposite end of the casing, a switch for starting and stopping the motor and mounted on the casing, and hand-operated means for actuating the switch and including a lever having a portion ulcrumed within the handle, said handle having lan opening adjacent the lever for the reception'or` a pin or plug to hold the lever in the closed condition of the switch.

7. An electric tool comprising a motor casing, a tool spindle projecting at one end of the casing, aremovable head for the op posite end of the casing, a handle of the hand-saw type carried by the head, the grip portion of the handle being hollow and provided with a longitudinal slot in its front side, a switch for starting and stopping the motor and carried by the motor casing, means for manually operating the switch including a lever fulcrumed intermediate of its ends within the hollow portion of the handle and provided with the finger portion lying between thehan'dle and the removable head, a spring for yieldably maintaining the inger portion of the lever at its forward limit, a link extending through a bore in the handle and having. one end pivotallv connected to a movable part of the switch, and

a screw threaded pivot pin detachably oonnecting the linkto the lever, the handle being provided with an opening to give access to the removable pivot connection.

8. An electric tool comprising a motor casing, a tool spindle, a handle on the casing, a switch for starting and stopping the motor and mounted on the casing, a hand operated means for actuating the switch and including a lever having a portion fulcrumed `within the handle, and said handle having an opening adjacent the lever for tool spindle projecting at one end of the' casing, a removable handle for the opposite end o f the casing, a Switch for starting and stopping the motor and carried by the casing and in front of the handle, a hand-Y y operated lever Jfulcrumed upon the handle, and a detachable operating connection between the lever and the switch.

CHARLES B. BENNETT.

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